diff --git a/PocketSharp/Models/Parameters/Parameters.cs b/PocketSharp/Models/Parameters/Parameters.cs
index 87bea45..a8b11b1 100644
--- a/PocketSharp/Models/Parameters/Parameters.cs
+++ b/PocketSharp/Models/Parameters/Parameters.cs
@@ -65,7 +65,7 @@ namespace PocketSharp.Models
         // convert DateTime to UNIX timestamp
         if (value is DateTime)
         {
-          value = (int)((DateTime)value - new DateTime(1970, 1, 1)).TotalSeconds;
+          value = (int)((DateTime)value - new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc)).TotalSeconds;
         }
 
         parameterDict.Add(name, value.ToString());
diff --git a/PocketSharp/Utilities/JsonExtensions.cs b/PocketSharp/Utilities/JsonExtensions.cs
index 7ff436c..fe2302a 100644
--- a/PocketSharp/Utilities/JsonExtensions.cs
+++ b/PocketSharp/Utilities/JsonExtensions.cs
@@ -32,8 +32,9 @@ namespace PocketSharp
   {
     public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
     {
-      DateTime epoc = new DateTime(1970, 1, 1);
-      var delta = (DateTime)value - epoc;
+      DateTime date = (DateTime)value;
+      DateTime epoc = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
+      var delta = date - epoc;
 
       writer.WriteValue((long)delta.TotalSeconds);
     }